Authenticable digital code and associated systems and methods

ABSTRACT

An authenticable digital code includes a printable medium, a machine-readable digital code, formed on the printable medium, that graphically represent information, and at least one security signature positioned relative to the machine-readable digital code. The security signature includes a fluorescent material that, when excited by light of a first wavelength, fluoresces and emits light at a second wavelength that is different from the first wave length. Authenticity of the authenticable digital code is determined by detecting, when the authenticable digital code is illuminated by light of the first wavelength, light of the second wavelength at a position relative to the machine-readable digital code.

RELATED APPLICATIONS

This application claims priority to U.S. Patent Application Ser. No.62/354,582, titled “Authenticable Digital Code and Associated Systemsand Methods,” and filed Jun. 24, 2016, which is incorporated herein byreference.

BACKGROUND

Products are typically packaged with a machine-readable code (e.g., a QRcode, a barcode, a data matrix, and other similar codes) that identifiesthe product. For example, the machine-readable code may includemanufacturer identification (ID), a product ID, a product serial number,and so on. However, the machine-readable code cannot provideauthentication of the product it is attached to, even when containing aunique serial number, since the code itself is easily copied. That is,there is no way to ascertain whether the machine-readable code beingscanned is authentic or an image duplicate. Thus, even where a consumerproduct is marked with the machine-readable code, the code provides noindication of authenticity of the object.

Many mobile phones and tablets include cameras for capturing pictures.These cameras typically use a CMOS (complementary metal-oxidesemiconductor) sensor with an infrared (IR) cut-off filter that isdesigned to block near-IR photons from reaching the imaging sensor,while passing visible light. The IR cut-off filter prevents IR radiationfrom distorting images formed from visible radiation. While this resultsin more natural looking images, conventional mobile devices aretherefore unsuitable for detecting fluorescent emission at IRwavelengths without removal of the included IR cut-off filter.

Many phosphors emit visible light when excited by Ultraviolet (UV)light. However, mobile phones cannot generate UV light at theappropriate wavelength and intensity to excite these phosphors. Thus,mobile phones have not been considered suitable for visible lightauthentication.

SUMMARY

In one embodiment, an authenticable digital code includes a printablemedium, a machine-readable digital code, formed on the printable medium,that graphically represents information, and at least one securitysignature having a fluorescent material that, when excited by firstlight at a first wavelength, fluoresces and emits second light at asecond wavelength, that is different from the first wavelength. Thesecond light being emitted at a position relative to themachine-readable digital code for indicating authenticity of theauthenticable digital code.

In another embodiment, a method manufactures an authenticable digitalcode. A code print image that graphically represents information of theauthenticable digital code is generated and printed onto a printablemedium using one or more visible inks to form a machine-readable digitalcode. A security print image that graphically represents a securitysignature is generated and printed onto the printable medium in aposition relative to the code print image using a fluorescent materialthat, when excited by first light at a first wavelength, fluoresces andemits second light at a second wavelength that is different from thefirst wave length, the second light emitting at a position relative tothe machine-readable digital code for indicating authenticity of theauthenticable digital code.

In another embodiment, a system for authenticating an authenticabledigital code includes a processor, a non-transitory memorycommunicatively coupled with the processor, a camera controlled by theprocessor and having a field of view, a light emitting displaycontrolled by the processor that emits first light into thefield-of-view of the camera, and software having machine-readableinstructions stored in the memory that, when executed by the processor,are capable of: controlling the light emitting display to emit the firstlight of a first wavelength, controlling the camera to capture an imageof the authenticable digital code positioned within the field of viewand illuminated by the first light, analyzing the image to detect secondlight of a second wavelength at a position within the image relative tothe machine-readable digital code resulting from fluorescence of asecurity signature on the authenticable digital code, and decoding andauthenticating the authenticable digital code based upon the positionand the second wavelength.

In another embodiment, a method authenticates an authenticable digitalcode. A light emitting display is controlled to emit first light of afirst wavelength. A camera is controlled to capture an image of theauthenticable digital code illuminated by the first light. The image isanalyzed to detect second light of a second wavelength at a positionwithin the image relative to a machine-readable digital code of theauthenticable digital code and resulting from fluorescence of a securitysignature of the authenticable digital code. The machine-readabledigital code of the authenticable digital code is decoded andauthenticated based upon the position of the second light in the imagerelative to the machine-readable digital code within the image.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a prior-art machine-readable digital code in the form of aQR code that includes a central logo.

FIG. 2 is a schematic illustrating one exemplary authenticable digitalcode that includes a machine-readable digital code and a securitysignature formed on a printable medium, in an embodiment.

FIG. 3 shows one exemplary authentication device for authenticating theauthenticable digital code of FIG. 2, in an embodiment.

FIG. 4 is a flowchart illustrating one exemplary method forauthenticating the authenticable digital code of FIG. 2, in anembodiment.

FIG. 5 shows exemplary positions, shapes and sizes of the securitysignature relative to the machine-readable code of FIG. 2.

FIG. 6 is a color space graph displaying exemplary captured colorresponses from the security signature of FIG. 2 for four differentexcitation frequencies, in an embodiment.

FIG. 7 shows one exemplary authenticable digital code that includes amachine-readable digital code and a security code area formed on aprintable medium, in an embodiment.

FIG. 8 shows one exemplary authenticable digital code that includes amachine-readable digital code and a distributed security code areaformed on a printable medium, in an embodiment.

FIG. 9 shows one exemplary authenticable digital code that includes amachine-readable digital code and two security code areas formed on aprintable medium, in an embodiment.

FIG. 10 shows one exemplary system for producing the authenticabledigital code of FIGS. 2, 5, 7, 8, and 9, in an embodiment.

FIG. 11 is a flowchart illustrating one exemplary method for generatingan authenticable digital code, in an embodiment.

DETAILED DESCRIPTION Visual Fluorescence Code Validation

FIG. 1 shows a prior-art machine-readable digital code 100 in the formof a QR code 102 that includes a central logo 104, illustratively shownas a stylistic letter “A.” As known in the art, QR code 102 has threeposition markers 106(1)-(3), one or more alignment markers 108, and adata and timing area 110 that form the remainder of QR code 102. QR code102 is typically printed in a black pigment on a white background tomake it readable by a reading device. However, as noted above, there isno way to determine whether machine-readable digital code 100 (e.g., QRcode 102) is an original or replica thereof, since the replica providesthe same information to the reading device as does the original.

In the following figures, machine-readable digital codes are shownhashed, rather than solid black, for clarity of illustration. However,these hashed areas represent solid black or other colors as known in theart of machine-readable digital codes.

FIG. 2 is a schematic illustrating one exemplary authenticable digitalcode 200 that includes a machine-readable digital code 202 and asecurity signature 204 formed on a printable medium 201.Machine-readable digital code 202 is a graphical representation ofinformation that is optically readable by a conventional prior-artreading device, using visible light for example. In the example of FIG.2, machine-readable digital code 202 includes the same information as QRcode 102 of FIG. 1. Machine-readable digital code 202 may take othergraphical forms without departing from the scope hereof.

Security signature 204 is positioned relative to machine-readabledigital code 202 and formed of a fluorescent material that, in responseto light of a first frequency, emits light at a second frequency. In oneembodiment, the fluorescent material of security signature 204 includesa phosphor that emits red light when illuminated by blue light. However,when illuminated by regular white light, security signature 204 is noteasily discerned from markings of machine-readable digital code 202. Inone embodiment, security signature 204 includes both a reflectivecomponent and a fluorescent component. For example, phosphor micro-dotsused to form security signature 204 may be formed with a thin coating ofpigmented reflective material of a first color, such that securitysignature 204 appears to be of the first color when viewed under whitelight, but appears to be of a second color when illuminated by light ofonly a certain color (e.g., blue). In another example, the quantity ofphosphor microdots within security signature 204 is relatively small,and thus these phosphor micro-dots have lower visibility that otherincludes pigments of security signature 204 when viewed under whilelight. The reflective component may include a color pigment that allowssecurity signature 204 to be visible under normal illuminationconditions (e.g., white light and/or day light). The fluorescentcomponent allows security signature 204 to be detected when illuminatedby light of a certain color.

In one embodiment, security signature 204 is configured to appearsubstantially white under normal illumination and is positioned over awhite portion of machine-readable digital code 202. In an alternateembodiment, security signature 204 is configured to appear substantiallyblack under normal illumination and is positioned over a black portionof machine-readable digital code 202. In the example of FIG. 2, the areaof security signature 204 is approximately equal to the arearepresenting one “bit” of information of machine-readable digital code202. However, as shown in FIG. 5 and described below, security signature204 may have other shapes and sizes without departing from the scopehereof.

FIG. 3 shows one exemplary authentication device 302 for authenticatingauthenticable digital code 200. Device 302 includes a processor 304 amemory 306 communicatively coupled with processor 304, a camera 308communicatively coupled with processor 304, and a display 310communicatively coupled with processor 304 via interface electronics312. Display 310 is of a type that emits light, such as selected fromthe group including: LCD, LED, and OLED. Device 302 is for example amobile device and may represent one or more of: a smart phone, apersonal digital assistant, a tablet computer, a laptop computer, anotebook computer, an MP3 player, and a smart television.

Camera 308 is positioned such that objects (e.g., authenticable digitalcode 200) positioned within the field of view of camera 308 are also infront of, and illuminated by light from, display 310. For example, wheredevice 302 is a smart phone, camera 308 is a forward facing camera ofthe smart phone and display 310 is the display of the smart phone wherethe camera and the display face the same direction. Display 310 iscontrolled by processor 304 to display graphical and textual informationand may incorporate touch sensitivity to receive input from a user.

Device 302 also includes an authenticator 314, implemented asmachine-readable instructions stored in memory 306 and executed byprocessor 304, that controls camera 308 and display 310 to authenticateauthenticable digital code 200. In one embodiment, where device 302 is asmart phone or tablet type device, authenticator 314 is an “app” that isdownloaded and run on the smart phone or tablet type device. Device 302may be other such similar devices without departing from the scopehereof. It should be noted that device 302 requires no additionalfilters or light sources when authenticating digital code 200.

As shown in FIG. 3, authenticable digital code 200 is positioned infront of both camera 308 and display 310 such that authenticable digitalcode 200 is within a field of view 309 of camera 308 and receives light340 emitted from at least a portion 311 of display 310. Authenticator314 controls display 310 to selectively illuminate authenticable digitalcode 200 and controls camera 308 to capture one or more images 332 ofauthenticable digital code 200 while illuminated. Authenticator 314 thenprocesses images 332 to determine authenticity of authenticable digitalcode 200.

Authenticable digital code 200 is positioned a distance 342 from camera308 and display 310 such that light 340 from display 310 is moreinfluential upon authenticable digital code 200 than ambient light 344.However, depending upon capabilities of camera 308 and display 310,distance 342 may be outside an operational focus range of camera 308,such that a raw image 332(1) captured of code 200 is blurred.Authenticator 314 may therefore include a de-blur algorithm 316 that isinvoked to de-blur raw image 332(1) to form de-blurred first image332(2). Optionally, authenticator 314 may also include a de-skewalgorithm 318 that may be invoked by authenticator 314 to de-skew andstraighten an image of authenticable digital code 200 within de-blurredfirst image 332(2), such that the captured image of authenticabledigital code 200 is consistently shaped, sized and oriented withinde-blurred first image 332(2).

First Authentication Level

At a first authentication level, device 302 detects presence of expectedfluorescence from security signature 204, wherein the detected presenceof fluorescence at the expected wavelength (frequency) indicates thefirst authentication level of digital code 200 has been passed. Whereonly simple authentication of authenticable digital code 200 isrequired, authenticable digital code 200 may be determined as authentic.

Second Authentication Level

Where stronger authentication of authenticable digital code 200 isneeded, further analysis of security signature 204 may be performed,once the presence of security signature 204 is verified. At a secondauthentication level, device 302 performs further evaluations ofsecurity signature 204 based upon position.

Within authenticable digital code 200, security signature 204 may bepositioned at a predefined location relative to machine-readable digitalcode 202. For example, as shown in FIG. 2, security signature 204 iswithin code 202 and positioned relative to position markers 206 andalignment marker 208 such that by identifying the location of two ormore of position markers 206 and alignment marker 208 within a capturedimage (e.g., image 332), the location of security signature 204 withinthe image may also be determined. Where security signature 204 is notpositioned at the predefined location, authenticable digital code 200 isnot authenticated. In one embodiment, the predefined relative positionof security signature 204 relative to machine-readable digital code 202does not change for different information stored within themachine-readable digital code 202.

In one embodiment, the location of security signature 204 relative tomachine-readable digital code 202 is predefined based upon informationwithin machine-readable digital code 202. For example, for a firstproduct identified by a first machine-readable digital code 202,security signature 204 may have a first position relative tomachine-readable digital code 202 that is different from a secondposition of security signature 204 for a second machine-readable digitalcode that identifies a different product. That is, system 300 may decodemachine-readable digital code 202 to determine a predefined location forsecurity signature 204, prior to authenticating the authenticabledigital code 200.

In one example of operation, where the detected position of securitysignature 204 relative to machine-readable digital code 202 does notmatch the predefined position indicated by information decoded frommachine-readable code 202, authenticator 314 may determine thatauthenticable digital code 200 is not authentic. Thus, the position ofsecurity signature 204 within authenticable digital code 200 is thusused as an additional level of protection against copying ofauthenticable digital code 200.

As shown in FIG. 3, authenticator 314 may include a decode algorithm 320that operates to decode machine-readable digital code 202 ofauthenticable digital code 200 to generate code information 336.

FIG. 4 is a flowchart illustrating one exemplary method 400 forauthenticating authenticable digital code 200 of FIG. 2. Method 400 isimplemented in authenticator 314 of FIG. 3, for example.

In step 402, method 400 controls the display of a reading device to emitwhite light. In one example of step 402, authenticator 314 controlsportion 311 of display 310 to emit white light. In step 404, method 400controls the camera to capture an image. In one example of step 404,authenticator 314 controls camera 308 to capture image 332(1) ofauthenticable digital code 200. In step 406, method 400 performs atleast one of de-blur, de-skew, and sizing of the image and stores it asa first image. In one example of step 406, authenticator 314 uses one orboth of de-blur algorithm 316 and de-skew algorithm 318 to de-blur,de-skew, and size image 332(1) to form de-blurred first image 332(2)such that the image of code 200 is of a standard orientation and size.In step 408, method 400 decodes the first image to generate codeinformation. In one example of step 408, authenticator 314 invokesdecode algorithm 320 to decode information of machine-readable digitalcode 202 from de-blurred first image 332(2) to form code information336.

In step 410, method 400 controls the display to emit light at a specificfrequency (wavelength, color, etc.). In one example of step 410,authenticator 314 controls display 310 to emit blue light 340 fromportion 311. In step 412, method 400 controls the camera to capture animage. In one example of step 412, authenticator 314 controls camera 308to capture image 332(1) of authenticable digital code 200 whileilluminated by light 340. In step 414, method 400de-blurs/de-skews/sizes the image and stores it as a second image. Inone example of step 414, authenticator 314 uses one or both of de-bluralgorithm 316 and de-skew algorithm 318 to de-blur, de-skew, and sizeimage 332(1) to form de-blurred second image 332(3) such that the imageof code 200 is of a standard orientation and size.

In step 416, method 400 determines a frequency of fluorescence in thesecond image. In one example of step 416, authenticator 314 analyzesde-blurred second image 332(3) to determine a frequency 334 offluorescence from security signature 204 when illuminated by blue light.

In step 418, method 400 determines authenticity based upon thedetermined frequencies. In one example of step 418, authenticator 314compares frequency 334 to one or more predefined expected fluorescencefrequencies, where if the frequencies match, code 200 is determined asauthentic.

Steps 420 and 422 are optional. If included, in step 420, method 400determines a position of the security signature relative to themachine-readable digital code. In one example of step 420, authenticator314 determines, from one or both of images 332(2) and 332(3), a positionof security signature 204 relative to two or more of position markers206 and alignment marker 208. If included, in step 422, method 400determines authenticity based upon the determined position. In oneexample of step 422, authenticator 314 determines code 200 to beauthentic when the determined position of security signature 204relative to position markers 206 and alignment marker 208 is correctwith respect to the predefined location.

Steps 410 through 418 may repeat with different specific frequencies forthe light emitted from the display to determine multiple frequencies offluorescence within the captured image of step 412. The step ofdetermining authenticity (418) is based upon multiple frequencies. Seefor example FIG. 6 and the associated description below.

FIG. 5 shows exemplary positions, shapes and sizes of security signature204 relative to machine-readable code 202. In a first example, securitysignature 204(1) is shaped, sized and positioned over a logo (e.g., logo104). In a second example, security signature 204(2) is shaped, sizedand positioned over an outer portion of a position marker 206 (e.g.,position marker 206(3)). In a third example, security signature 204(3)is shaped, sized and positioned between portions of a position marker206 (e.g., position marker 206(1)). In a fourth example, securitysignature 204(4) is shaped, sized and positioned over an inner portionof a position marker 206 (e.g., position marker 206(3)). In a fifthexample, security signature 204(5) is shaped, sized and positioned overan inner portion of an alignment marker 208. The shape and size ofsecurity signature 204 is not limited to the shown examples and may bepositioned elsewhere on machine-readable code 202 without departing fromthe scope hereof.

Multiple Frequency Response Analysis

In one embodiment, authenticator 314 controls camera 308 to captureimages of code 200 when illuminated by light 340 of differingfrequencies (e.g., different colors emitted from display 310).Authenticator 314 then determines the fluorescence response fromsecurity signature 204 for each of the different frequencies used toexcite the fluorescence.

Detailed Response Analysis

FIG. 6 is a color space graph 600 having three axes, red (R), green (G),and blue (B), and displaying exemplary determined responses 602 fromsecurity signature 204 for four different excitation frequencies.Authenticator 314 controls camera 308 to capture a first image ofauthenticable digital code 200 while controlling display 310 to emitlight of a first frequency from at least portion 311. Authenticator 314then analyses this first image to determine a first color, plotted asresponse 602(1) on graph 600, emitted by security signature 204.Authenticator 314 repeats this process, emitting light of second, thirdand fourth colors from at least portion 311 of display 310 whilecapturing images of authenticable digital code 200, and determiningsecond, third, and fourth colors, plotted as responses 602(2), 602(3),and 602(4), respectively, on graph 600. As shown, the detected color ofsecurity signature 204 varies, depending upon the color of theilluminating light. This response is unique to the composition ofsecurity signature 204, and thus by determining the color response formultiple different illuminations colors, authenticator 314 may betterauthenticate authenticable digital code 200. As described above,phosphor micro-dots may be coated with a pigmented material to influencethe response of security signature 204 to different illuminatingwavelengths. Where a color response is not as expected for a particularcolor of light, authenticator 314 may determine that the presenteddigital code is not authentic, even when it does incorporate afluorescent material.

Secondary Security Codes

FIG. 7 shows one exemplary authenticable digital code 700 that includesa machine-readable digital code 702 and a security area 704 formed on aprintable medium 701. Machine-readable digital code 702 is similar tomachine-readable digital code 202 of FIG. 2, and represents a QR code inthis example. Security area 704 is positioned relative tomachine-readable digital code 702 and includes a fluorescent material706 that, in response to light of a first frequency, emits light at asecond frequency. In one embodiment, fluorescent material 706 emits redlight when illuminated by blue light. Fluorescent material 706 may alsobe configured such that, when illuminated by regular white light,security area 704 is not easily discerned from markings ofmachine-readable digital code 702.

Fluorescent material 706 provides authentication levels similar to thosedescribed above, based upon presence, and optionally position, offluorescent material 706 with machine-readable digital code 702. Thatis, wherein detection of fluorescence from fluorescent material 706 at asecond frequency (e.g., red) when illuminated by light at a firstfrequency (e.g., blue) indicates a first level of authenticity ofauthenticable digital code 700, and position of the detectedfluorescence relative to machine-readable digital code 702 indicates asecond level of authenticity.

Further, location of detected fluorescence from fluorescent material 706is decoded, based upon position of detected fluorescent material 706within security area 704 (e.g., similar to decoding of machine-readabledigital code 702), to generate a security code value (e.g., securitycode value 338 stored in memory 306 of FIG. 3). This security code value338 provides a next level of authentication. In the example of FIG. 7,security area 704 contains twenty-one whole areas that correspond tobits of security code value, where presence of fluorescent material 706indicates a corresponding bit value of one. Security area 704, andthereby the number of bits contained therein, may be greater or fewerwithout departing from the scope hereof. Further, security area 704 mayinclude error identification and/or error correction bits withoutdeparting from the scope hereof.

In one embodiment, security code value 338 is a checksum value forinformation contained within machine-readable digital code 702.

In one embodiment, security code value 338 is used to further decodeinformation contained within machine-readable digital code 702. Forexample, security code value 338 may provide a hash value for decryptingdata read from machine-readable digital code 702 to produce usefulinformation. That is, conventional reading of machine-readable digitalcode 702 provides a character sequence that is meaningless untildecrypted using security code value 338 with a decryption algorithm.

FIG. 8 shows one exemplary authenticable digital code 800 that includesa machine-readable digital code 802 and a distributed security code areacontaining a distributed security code value formed on a printablemedium 801. Authenticable digital code 800 is similar to authenticabledigital code 700, wherein location of detected fluorescence from afluorescent material 804 is used to determine a security code value(e.g., security code value 338). Other areas and methods of decodingfluorescence from fluorescent material 804 based upon location of thedetected fluorescence relative to machine-readable digital code 802 maybe used without departing from the scope hereof.

In another embodiment, not shown, fluorescent material 804 defines oneor more position markers and alignment markers, such that informationmay be decoded from detected fluorescence without reference tomachine-readable digital code 802. That is, fluorescent material 804 ispositioned independently of machine-readable digital code 802, and maybe decoded without reference to machine-readable digital code 802.

Multiple Security Signatures

Advantageously, the use of display 310 to illuminate authenticabledigital code 200 easily allows light of different wavelengths to beselectively used. FIG. 9 shows one exemplary authenticable digital code900 that is similar to authenticable digital code 700 of FIG. 7, havinga machine-readable digital code 902, and including two security areas904(1), 904(2) that each include includes a fluorescent material 906(1)and 906(2), formed on a printable medium 901. Fluorescent material906(1), in response to light of a first frequency, emits light at asecond frequency. For example, fluorescent material 906(1) emits redlight when illuminated by blue light. Fluorescent material 906(2), inresponse to light of a third frequency, emits light at a fourthfrequency. For example, fluorescent material 906(2) emits green lightwhen illuminated by blue light. Fluorescent materials 906 may also beconfigured such that, when illuminated by regular white light, securitycode areas 904 are not easily discerned from machine-readable digitalcode 902. As noted above, the phosphor may be formed as micro-dots thatare coated with a thin colored pigment that modifies the appearance ofthe phosphor when not fluorescing. In an alternate embodiment, one ofthe two security areas 904(1), 904(2) is configured to emit light at aninfra-red (IR) wavelength in response to light of a particularfrequency, and camera 308 is configured to sense light at both visibleand IR wavelengths (see for example FIG. 5 and associated description ofAppendix B of U.S. Patent Application Ser. No. 62/354,582).

Fluorescent materials 906 provide authentication levels similar to thosedescribed above, based upon presence, and optionally position, offluorescent materials 906 with machine-readable digital code 902. Thatis, wherein detection of fluorescence from fluorescent material 906(1)at a second frequency (e.g., red) when illuminated by light at a firstfrequency (e.g., blue), and/or detection of fluorescence fromfluorescent material 906(2) at a fourth frequency (e.g., green) whenilluminated by light at the third frequency (e.g., blue) indicates afirst level of authenticity of authenticable digital code 900, andposition of the detected fluorescence relative to machine-readabledigital code 902 indicates a second level of authenticity.

Further, location of detected fluorescence from fluorescent materials906 is decoded, based upon position of detected fluorescent material 906within security code areas 904 (e.g., similar to decoding ofmachine-readable digital code 902), to generate first and secondsecurity code values that operate together to for a next level ofauthentication.

Thus, the versatility of using a display 310 to emit light at desiredfrequencies allows the different phosphors to be easily detected anddifferentiated from machine-readable digital code 902. In one example ofoperation, authenticator 314 controls camera 308 to capture a firstimage of authenticable digital code 900 while controlling display 310 toemit white light. Authenticator 314 then controls camera 308 to capturea second image of authenticable digital code 900 while controllingdisplay 310 to emit light at a first frequency, and then authenticator314 controls camera 308 to capture a third image of authenticabledigital code 900 while controlling display 310 to emit light at thethird frequency. Authenticator 314 then uses one or more of de-bluralgorithm 316, de-skew algorithm 318 and decode algorithm 320 to decodeeach of the first, second and third captured images.

Information decoded from each security code area 904(1) and 904(2) maythen be used as additional authentication values, or may be used tounencrypt information of machine-readable digital code 902.

FIG. 10 shows one exemplary system 1000 for generating an authenticabledigital code 1002. Authenticable digital code 1002 may represent one ormore of authenticable digital codes 200, 700, 800, and 900 of FIGS. 2,5, 7, 8 and 9, respectively.

System 1000 includes a printing machine 1004 and a computer 1006 thatincludes a processor 1008 communicatively coupled with a memory 1010. Acode image generator 1012 includes machine-readable instructions thatare stored within memory 1010 and executed by processor 1008 to generateone or more code print images 1016 that correspond to themachine-readable digital code (e.g., machine-readable digital code 202,702, 802, and 902) portion of authenticable digital code 1002. Forexample, code image generator 1012 may receive digital code information1020 from an external source and automatically generate one or more codeprint images 1016 therefrom using an algorithm. In one embodiment,generator 1012 encrypts digital code information 1020 based upon asecurity code value 1022 (optionally received from an external source)and thus, information within the machine-readable digital code of code1002 does not directly reflect digital code information 1020. Whereprinted using a CMYK process, known in the art, code print images 1016may be formed of four registered images, one for each of cyan, magenta,yellow, and black.

Computer 1006 also includes a security image generator 1014 thatincludes machine-readable instructions stored in memory 1010 andexecuted by processor 1008 to generate a security print image 1018 basedupon one or both of security code value 1022 and a security signatureposition 1024. For example, where code 1002 represents code 200 of FIG.2, generator 1014 utilizes security signature position 1024 to generateimage 1018 with security signature 204 positioned relative tomachine-readable digital code 202 within image 1016.

In another example, where code 1002 represents codes 700 and 900 ofFIGS. 7 and 9, generator 1014 utilizes security signature position 1024and security code value 1022 to generate image 1018 with a security codearea (e.g., security code areas 704 and 904) positioned relative tomachine-readable digital code 202 within image 1016 and definingposition of fluorescent material (e.g., fluorescent materials 706 and906) based upon security code value 1022, respectively.

Code print images 1016 and security print images 1018 are then used(either directly or indirectly through use of plates and screensgenerated from images 1016 and 1018) by printing machine 1004 to printcode 1002 using optical inks 1030, security inks 1032 into a medium1034. Security inks 1032 contain specifically selected phosphor(s) thatfluoresce when illuminated by visible light of a certain color. Printingmachine 1004 is for example a conventional printing apparatus using CMYKtype printing where the security ink(s) 132 are printed in an additionalprinting step (e.g., CMYK+ONE), as known in the art of printing, that,by using security inks 1032, may be used to print authenticable digitalcode 1002. Where two or more different fluorescent materials (e.g.,phosphors, or coated phosphor micro-dots) are used for two or moredifferent security codes (see code 900 of FIG. 9), additional printsteps may be added. Further, a top layer may be added to code 1002 forprotection against moisture and wear, as known in the art of printing.

FIG. 11 is a flowchart illustrating one exemplary method 1100 formanufacturing an authenticable digital code. Method 1100 is for exampleimplemented within generators 1012 and 1014 of computer 1006 andprinting machine 1004 of system 1000 of FIG. 10.

In step 1102, method 1100 receives information for the machine-readabledigital code. In one example of step 1102, computer 1006 receivesdigital code information 1020. In step 1104, method 1100 generates amachine-readable digital code from the information. In one example ofstep 1104, code image generator 1012 generates code print image 1016based upon a graphical representation of digital code information 1020.In another example of step 1104, code image generator 1012 firstencrypts digital code information 1020 based upon security code value1022, and then generates code print image 1016 as a graphicalrepresentation of the encrypted information.

In step 1106, method 1100 determines a location of the security area. Inone example of step 1106, security image generator 1014 determines alocation of security signature 204 relative to machine-readable digitalcode 202 based upon information within digital code information 1020. Inanother example of step 1106, security image generator 1014 determines alocation of security area 704 (or security areas 904) based upon digitalcode information 1020. In another example of step 1106, a location ofsecurity areas 704, 904, is predefined within security image generator1014.

Step 1108 is optional. If included, in step 1108, method 1100 determinesthe security code. In one example of step 1108, security image generator1014 determines security code value 1022 from received input. In anotherexample of step 1108, security code value 1022 is predefined withinsecurity image generator 1014. In another example of step 1108, securityimage generator 1014 determines security code value 1022 from digitalcode information 1020.

In step 1110, method 1100 generates security print image from thesecurity code. In one example of step 1110, security image generator1014 generates security print image 1018 based upon security code value1022.

In step 1112, method 1100 prints the code print image to a printablemedium. In one example of step 1112, printing machine 1004 is controlledto print code print image(s) 1016 to medium 1034. In step 1114, method1100 prints the security print image to the same printable medium. Inone example of step 1114, printing machine 1004 is controlled to printsecurity print image(s) 1018 to medium 1034, registered to the printedcode print image 1016.

Steps of method 1100 may be performed in a different order withoutdeparting from the scope hereof.

Changes may be made in the above methods and systems without departingfrom the scope hereof. It should thus be noted that the matter containedin the above description or shown in the accompanying drawings should beinterpreted as illustrative and not in a limiting sense. The followingclaims are intended to cover all generic and specific features describedherein, as well as all statements of the scope of the present method andsystem, which, as a matter of language, might be said to falltherebetween.

What is claimed is:
 1. An authenticable digital code, comprising: aprintable medium; a machine-readable digital code, formed on theprintable medium, that graphically represents information; and at leastone security signature comprising a fluorescent material that, whenexcited by first light at a first wavelength, fluoresces and emitssecond light at a second wavelength, that is different from the firstwavelength, the second light emitting at a position relative to themachine-readable digital code for indicating authenticity of theauthenticable digital code.
 2. The authenticable digital code of claim1, the fluorescent material being configured to fluoresce and emit thesecond light based upon the first light being generated by a mobiledevice without additional light sources or filters.
 3. The authenticabledigital code of claim 1, the first wavelength corresponding to a bluecolor and the second wavelength corresponding to a red color.
 4. Theauthenticable digital code of claim 1, the position of the securitysignature relative to the machine-readable digital code being based uponthe information.
 5. The authenticable digital code of claim 1, themachine-readable digital code being selected from the group including: abarcode, a matrix code, and a QR code.
 6. The authenticable digital codeof claim 1, the security signature comprising a graphical representationof a security code value that indicates authenticity of theauthenticable digital code.
 7. The authenticable digital code of claim6, the security code value being based upon the information.
 8. Theauthenticable digital code of claim 6, the information being encryptedand associated with the security signature being related such that theinformation may be decrypted by the security code value.
 9. Theauthenticable digital code of claim 6, the security signature furthercomprising a second graphical representation of a second security codevalue that further indicates authenticity of the authenticable digitalcode.
 10. The authenticable digital code of claim 9, the secondgraphical representation being printed to the printable medium using asecond fluorescent material, that, when excited by third light of athird wavelength that is different from the first and secondwavelengths, fluoresces and emits fourth light at a fourth wavelengththat is different from the first, second and third wavelengths, thefourth light at a second position relative to the machine-readabledigital code indicating authenticity of the authenticable digital code.11. The authenticable digital code of claim 1, the first and secondwavelengths corresponding to visible light.
 12. A method formanufacturing an authenticable digital code, comprising: generating acode print image that graphically represents information of theauthenticable digital code; printing the code print image onto aprintable medium using one or more visible inks to form amachine-readable digital code; generating a security print image thatgraphically represents a security signature; printing the security printimage onto the printable medium in a position relative to the code printimage using a fluorescent material that, when excited by first light ata first wavelength, fluoresces and emits second light at a secondwavelength that is different from the first wave length, the secondlight emitting at a position relative to the machine-readable digitalcode for indicating authenticity of the authenticable digital code. 13.A system for authenticating an authenticable digital code, comprising: aprocessor; a non-transitory memory communicatively coupled with theprocessor; a camera controlled by the processor and having a field ofview; a light emitting display controlled by the processor that emitsfirst light into the field-of-view of the camera; and softwarecomprising machine-readable instructions stored in the memory that, whenexecuted by the processor, are capable of: controlling the lightemitting display to emit the first light of a first wavelength;controlling the camera to capture an image of the authenticable digitalcode positioned within the field of view and illuminated by the firstlight; analyzing the image to detect second light of a second wavelengthat a position within the image relative to the machine-readable digitalcode resulting from fluorescence of a security signature on theauthenticable digital code; and decoding and authenticating theauthenticable digital code based upon the position and the secondwavelength.
 14. The system of claim 13, the processor, the memory, thelight emitting display and the camera being part of a device selectedfrom the group of mobile devices including a smartphone, a tabletcomputer, a laptop computer, a notebook computer, an MP3 player, and apersonal digital assistant.
 15. The system of claim 13, the softwarefurther comprising machine-readable instructions that when executed bythe processor are capable of de-blurring the first image when theauthenticable digital code is positioned outside a focusing range of thecamera.
 16. The system of claim 13, the first and second wavelengthscorresponding to visible light.
 17. A method for authenticating anauthenticable digital code, comprising the steps of: controlling a lightemitting display to emit first light of a first wavelength; controllinga camera to capture an image of the authenticable digital codeilluminated by the first light; analyzing the image to detect secondlight of a second wavelength at a position within the image relative toa machine-readable digital code of the authenticable digital code andresulting from fluorescence of a security signature of the authenticabledigital code; and decoding and authenticating the machine-readabledigital code of the authenticable digital code based upon the positionof the second light in the image relative to the machine-readabledigital code within the image.